YES, there is the german word for "Voice Control" appearing on the screen. So this different from the Siri screen?
Nevertheless - at least the possibility for third person to use Voice recognition should be blocked. Imagine, Voice control starts (as with the one of my iP5) to connect a third person (or a child) with a contact in a foreign country for hours! Could cost you much!
If you have time enough to do this as a third person, you could try a lot of names and contacts and if you get the connection, you know that this person has at least contact with these names.
I don´t know if you can do more with the Voice control, but I think this might be the case…
a mighty instrument for wifes: They call the secret girl friend and because your name and phone number appears on her screen she starts to talk: "Hi Darling, the last weekend was beautiful - hope your wife doesn´t know for a long time! "
By any chance , do you do all of this with your phone connected to a/the charger?
When I tried SIRI (never worked for me) it would never do what I asked via voice control. Say, I asked it to play a certain song from my music library, instead it would dial a random number from my phone contacts.
Then I read someplace that SIRI doesn't work if you are charging. Don't know if that is true. (Makes no sense)
Anyway, SIRI has so far never worked for me and I no longer bother.